Process of producing waterproof concrete, specially for pavings



Patented May 27, 1930 UNITED STATES PATENT OFFICE RICHARD SCHUBERT, OF BREMEN, GERMANY No Drawing. Application filed March 10, 1928,.Seria1 No. 260,809, and in Germany December 23, 1927.

This invention relates to a process of producing water-proof concrete, specially for underground, underwater and reinforced concrete constructions and for dust-free pav- 5 ings. In concrete-pavings it has been proposed to us tar and asphalt coatings, which are however liable to become cracked and fissured and they must also be specially laid. Inconveniences are further that the surface gets soft, so that infectious substances and bacilla-carriers settle in the same and are difiicult to remove and are liable to cause the spread of diseases. It is further diflicult to clean such soft or cracked pavings.

The invention has for its object to produce a water-proof, dust-free and insulating concrete.

It consists in admixing with liquid coal-tar from 25% of an insulating material, for instance, asbestos or the like, which mixture is added toany of the commonly used concrete mixture ingredients and water at the time of use, the composition being laid at once as soon as produced and tamped, to make the mass of uniform density. The invention may be carried out in different manners.

The following is an example:

To the required quantity of liquid coal-tar from 2 to 5% of an insulating material, such as crushed asbestos or the like, is added.

lVith about 200 liters of tar 67 liters of the insulating material may be used. To one cubicmeter of any of the commonly used concrete mixtures of cement and sand, cement, sand and gravel etc., 8 to 15 liters of the dis tillate mixture areadded and intimately admixed therewith. 1 The preparation is made directly at the building site or site of use and the mass laid solidily and tamped at once. The usual concrete road formation may be employed. By the addition of insulating material the concrete-material is intimately combined With the liquid coal-tar.

Owing to the intimat binding'with coaltar-distillate the surface of the concrete is given greater durability, remains absolutelyconcrete body or surface, Which consists in first forming a binding and insulating mixture of liquid coal tar and an insulating material, adding the same to a concrete mixture and water at the time of making the latter, and then laying and tamping the resultant waterproof plastic mass.

2. The method of producing a Waterproof concrete body or surface, which consists in first forming a binding and insulating mixture of liquid coal tar and asbestos, adding the same to a concrete mixture and water at the time of making the latter, and then laying and tamping the resultant waterproof plastic mass.

In testimony whereof I afiix my signature.

RICHARD SCHUBERT. 

